The SEC filing states that Icahn disposed of the shares after concluding that better returns could be achieved by deploying capital elsewhere instead of waiting for the Dollar Tree transaction to close, or for a higher offer to emerge.

That deal is slated to close in early 2015.

Icahn issued a statement on Monday saying he was pleased with Dollar Tree’s offer, but he believes that there are a handful of potential buyers that could realize greater synergies through a combination with Family Dollar.

He remains “hopeful that one or more of them will surface as a result of (Monday’s) announcement.”

Tuesday's filing states that Icahn intends to continue studying the situation and may dispose of or acquire additional shares in the future based on the probability of a higher bid, market conditions or other factors.

Family Dollar’s stock closed at $74.50 on Tuesday, after trading as high as $76.35 during the day, driven by market speculation that another buyer may emerge. It dipped slightly to $74.36 in after-hours trading.

But that's up from $60.53 on June 6, when Icahn first disclosed his stake in the company.